周期性波纹通道内换热与流动的数值研究

采用曲线坐标系下压力与速度耦合的SIMPLER算法,数值研究了一种紧凑换热器中波纹通道内周期性充分发展的层流流动与换热情况,流动Re数的范围为100~1100,Pr数为0.7.计算考察了不同波纹高度、波纹间距对流动与换热的影响,并对模型参数进行了性能评价.计算结果表明,整体Nu数及fRe数随着流动Re数的增加而增加.随着波纹高度的增加或波纹间距的减小,换热增强,特别是在高Re数下波纹高度的增加更加强化换热.最佳波纹高度和间距分别为1.15 mm和13 mm.

A Numerical Study of Heat Transfer and Fluid Flow in a Periodically Wavy Channel

The periodically fully developed laminar heat transfer and fluid flow in a two-dimensional wavy channel in a compact heat exchanger are investigated numerically. Calculations are performed at Pr=0.7, in the range of Re=100~1100 with non-orthogonal non-staggered grids. The Semi-Implicit Method for Pressure Linked Equations Revised (SIMPLER) algorithm in the curvilinear body-fitted coordinates is used. The effect of the wavy height and distance on momentum and heat transfer is studied. Performance of model parameters is evaluated. It is shown that the overall Nusseh numbers and friction factors increase with the increase of Reynolds numbers. The friction factors and overall Nusseh numbers increase as increasing the wavy height or decreasing the wavy distance. The overall Nusseh numbers increase significantly with the wavy height, especially at high Reynolds numbers. The best wavy height and distance are 1.15 mm and 13 mm, respectively.